What is 7n-20=9(4n+1) ????

2 answers:

4 0

$7n-20=9(4n+1)\ \ \ \ | omit\ the\ bracket\\\\
7n-20=36n+9\ \ \ | add\ 20\\\\
7n=36n+29\ \ \ | subtract\ 36n\\\\
-29n=29\ \ \ | divide\ by\ -29\\\\
n=-1\\\\Solution\ is\ n=-1.$

Tresset [83]3 years ago

4 0

7n - 20 = 9(4n + 1)
7n - 20 = 36n + 9
-7n - 20 = 36n - 7n + 9
-20 = 29n + 9
-20 - 9 = 29n - 9
-29= 29n
29n = -29
n = -1

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